Driving back from work today and before I approach the roundabout in work I notice someone behind me beeping. I can't move over as there is a lorry next to me. Moving onto the next roundabout to pull onto the motorway he continues to chase my tail and beeping and then gets his phone out to, I assume, record me while has driving. Pulling onto the motorway from the slip road doing approx 60 now he pulls into my lane at a random sharp sideway. Causing me to break very hard and question what on earth has doing. He then keeps breaking very hard. This is all happening very quickly so bare in mind I am slowing down to avoid him but as initially it was approximately 60mph it's hard to just stop. Plus there are others behind me who've come off the slip road. I decide to call 999. I am giving them a detailed explanation as its happening etc. What has doing to me and now others too. The police basically said unless I have cctv it won't be pursued. I asked about the motorway camera etc and they said nope. We won't pursue it. AIBU to think this is why there are so many idiots on the road. Becasue nothing can or will be done. I am still shaken up by this and also worry I'll see him.again as he seems to work where I do.